During a survey of 23 wet heathland sites in Flanders (north Belgium) in 1999 and 2000, using both manual nest searching and pitfall traps as sampling techniques, we found 28 ant species. One species (Myrmica lonae) was new to the Belgian fauna and several rare species were encountered. Three ecological groups could be distinguished based on soil preference: the first group of species was characteristic of sandy soil, the second contained species that were more numerous on peat soil (with Sphagnum spp.), and the third group of species had no soil preference. Ant nest numbers increased strongly between 1999 and 2000, especially on the plots that were inundated during the winter of 1999-2000, but the number of ant species did not differ significantly between years. Ant nest density showed an optimum at a Purple Moor-grass (Molinia caerulea) cover of about 45%; the number of species did not show such an optimum. Pitfall traps yielded more species than manual nest searching; in particular temporary social parasites, species with a large foraging range and winged females from the surrounding habitats were missed by the latter technique. Finally, we give some recommendations for the conservation of, and suitable management measures for, ants on wet heathland.
The ants of the genus Protalaridris are revised based upon their morphology. Seven species are recognized; the type species (P. armata Brown, 1980) and six species described as new: P. aculeata Lattke & Alpert, sp. n., P. arhuaca Guerrero, Lattke & Alpert, sp. n., P. bordoni Lattke, sp. n., P. leponcei Delsinne & Lattke, sp. n., P. loxanensis Lattke, sp. n., and P. punctata Lattke, sp. n. The genus is patchily distributed in mesic forested areas from western Panama to northern Venezuela and along the Andes to the Amazon watershed of southwestern Peru. The generic description is modified to accommodate a short-mandibulate species. Sporadic biological observations of one long-mandibulate species suggest they are sit-and-wait ambush predators that open their jaws to approximately 180° when stalking. All species are described and imaged, an identification key and a distribution map is provided. Comparing the mandibular morphology of long-mandibulate Protalaridris with other extant and extinct ants bearing elongate, dorsoanterior arching mandibles suggests the supposed mandibular apex in these taxa is actually a hypertrophied, preapical tooth and their supposed basal mandibular tooth is the main mandibular shaft., John E. Lattke, Thibaut Delsinne, Gary D. Alpert, Roberto J. Guerrero., and Obsahuje bibliografii
Insights can be gained by analysing the feeding decisions of animals in terms of nutrient demands at a species or community level. Using carbohydrate and protein food baits, resource use and food preferences of Formica (Serviformica) lemani were determined at nine locations situated at different altitudes (1875 to 2400 m a.s.l.) in the alpine grassland belt above the tree line in Austria and northern Italy. F. lemani is the most common species of ant in this habitat. Sucrose baits placed around ant colonies were visited by significantly (3.9 times) more workers than protein baits. This indicates that sources of sugar (carbohydrate) are in short supply in the alpine zone, whereas availability of prey items appears to be less constraining. Overall, we recorded a decrease in the incidence of visits to baits from low (31.9% baits attracting ants at least once) to high altitudes (16.7%). Foraging ants never visited 51.5% of the baits exposed for periods of 75 min. This indicates that with increasing altitude competition for food among ant colonies becomes less intense in alpine grassland ant communities., Elia Guariento, Jan Martini, Konrad Fiedler., and Obsahuje bibliografii
Invasive species disrupt the organization and functioning of many ant communities. Little is known about ant assemblages formerly in areas invaded by the little fire ant. In this study, we surveyed the same areas and compared the ant communities there when an invasive species first colonized the areas and 10 years later, using the same methodology (quadrat and baiting). A total of 83,299 worker ants from 17 species or morphospecies, in 4 subfamilies and 10 genera were recorded in the two periods sampled. Seven ant species were found to co-occur with W. auropunctata while 12 species were collected in the same area 10 years later, with no W. auropunctata recorded in any of the traps. In the absence of W. auropunctata, the number and diversity of ant species increased and the ant communities were dominated by the African big-headed ant, Pheidole megacephala. Our findings indicate that the disappearance of W. auropunctata is probably related to population increases in P. megacephala associated with dramatic changes in landscape. Further studies at other invaded locations should be carried out in order to reveal the generality of these patterns throughout this country.
The Trophic Cascade Theory has been used to explain the organization of herbivorous insect communities in tropical ecosystems. In addition, the insect community associated with a species of plant can also be determined by the geographical distribution and taxonomic isolation of the plant. In this study, the following predictions about the number of herbivores associated with particular host plants were tested: (i) plant species belonging to large taxonomic groups with broad geographical distributions have a higher number, (ii) the abundance of ants negatively affects herbivore insect diversity, (iii) local plant diversity positively affects chewing herbivore diversity and (iv) local abundance of a specific host plant positively affects the diversity of sucking herbivores. The samples of insect herbivores were collected from 32 plants (16 plants of Erythroxylum suberosum and 16 of Qualea parviflora) by beating. A total of 71 ants (13 species) and 158 herbivorous insects (90 species) were collected from these two species of plants. The richness and abundance of the insect herbivores collected from E. suberosum differed from those collected from Q. parviflora. The abundance of ants negatively affected the diversity of sucking insects associated with E. suberosum. In addition, the interaction between the variables total plant richness per plot and ant abundance affected the diversity of chewing insects associated with E. suberosum. The density of Q. parviflora per plot affected the diversity of associated sucking insects. In addition, the interaction of the variables abundance of ants and abundance of Q. parviflora influenced the diversity of chewing insects. Our results indicate that there is no predominance of bottom-up or top-down forces in the organization of herbivorous insect communities in this area of tropical savanna, but the roles of these forces on insect communities are guild-dependent., Juliana Kuchenbecker, Marcílio Fagundes., and Obsahuje bibliografii
Soil and changes in vegetation may affect ant assemblages, but the relative importance of each in different habitats is not well characterized. In particular, information on the effects of ecological restoration on arthropods is scarce. It was decided, therefore, to study how reforestation may affect an ant assemblage. Ants were sampled in area that had been reforested and adjacent grassland using pitfall traps. Soil surface and vegetation were characterized. The disturbance of the vegetation caused by reforestation resulted in a decrease in the cover of Stipa tenacissima and Cistaceae and an increase in the cover of pine. The mechanical preparation of the site also resulted in changes in the soil surface, with an increase in the cover of stones and rocks. Ant species richness and abundance were greater at the reforested site than in the grassland and more species showed a positive than a negative response to reforestation. The underlying causes of this pattern are mainly related to changes in vegetation and structure of the soil surface and are associated with the increase in the cover of pine, which most probably provided additional food resources, and the greater cover of stones and rocks that provided more shelter for the ant assemblage., Chema Catarineu, Joaquín Reyes-López, Joan A. Herraiz, Gonzalo G. Barberá., and Obsahuje bibliografii
According to previous observations, it was hypothesized that the feeding behavior of some ant species would be deterred by a scavenger deterrent factor (SDF), whereas for other species it would not. The effects of the SDF were studied on 11 ant species in three different subfamilies: Dolichoderinae Forel, 1878, Formicinae Latreille, 1809, and Myrmicinae Lepeletier de Saint-Fargeau, 1835. The experiments were conducted from 2014-2015 in Davis, California, United States, Aydin, Turkey, and Duzce, Turkey. Five-day-old Heterorhabditis bacteriophora (Poinar, 1976), (Hb)-killed and freeze-killed Galleria mellonella (Linnaeus, 1758) were exposed to ant colonies in the field for 3 to 4 h. Seven ant species fed significantly less on Hb-killed insects than freeze-killed insect. On the other hand, there was no significant difference in cadaver consumption with five species, but Liometopum occidentale Emery, 1895 did consume a higher rate of Hb-killed insects than freeze-killed insects and was not deterred by SDF. It was also observed that four ant species took Hb-killed insects into the nests, but two Myrmicinae species, Pogonomyrmex subdentatus Mayr, 1870 and Messor meridionalis (André, 1883) removed the cadavers after 30 min, whereas two Formicinae species, Cataglyphis nodus (Brullé, 1833) and Formica fusca Linnaeus, 1758, retained the cadavers in the nest. It was assumed that the latter two species consumed both Hb-killed and freeze-killed insects. Further studies are needed to explain why L. occidentale C. nodus and F. fusca are not deterred by SDF., Baris Gulcu, Selcuk Hazir, Edwin E. Lewis, Harry K. Kaya., and Obsahuje bibliografii
Bilberry (Vaccinium myrtillus L.) is one of the dominant plants of the Fennoscandian boreal coniferous forest and constitutes a major food source for many insect herbivores. A common ant species in these forests is the wood ant Formica (Formica) aquilonia Yarrow, which preys heavily on other invertebrates within its territories. The aim of this study was to investigate whether aquilonia's predation on the insect herbivores may have indirect positive or negative effects on bilberry. Damage to the bilberry, its vegetative growth and reproduction were quantified in order to contrast localities close to (2 m) and far away from (50 m) ant nests.
Close to ant nests, herbivore damage to the bilberry was significantly lower and reproductive success, i.e. proportion of flowers succeeding to berries, significantly higher. The results of this study therefore suggest that distance to aquilonia nests, and thus predation from ants, can significantly affect herbivore damage to the bilberry and its reproductive success (supporting the hypothesis of a top down effect in this three-trophic-level system). Vegetative growth, i.e., density and biomass of current year shoots, and reproductive investment, i.e., proportion of current year shoots with flower, of the bilberry was, however, not affected by distance to ant nests, indicating that the bilberry can also compensate for losses due to herbivory.
In Europe there are only a few species of the syrphid fly Microdon, which live in the nests of various genera of ants. For most of these rare flies, details of their biology, larval behaviour and relationships with their hosts are still not yet well known. In this paper we present data on the life cycle, feeding behaviour and growth pattern of Microdon myrmicae, a social parasite of Myrmica ants and compare it with two species of Maculinea butterflies similarly parasitizing Myrmica ant colonies. M. myrmicae has three larval instars and overwinters as a third instar. Eggs and 1st instar larvae are ignored by ants, which indicate that they are “chemically insignificant”. 2nd and 3rd instar larvae feed on small ant brood. M.myrmicae larvae grow rapidly from May to July and later in the year the host colony only serves as shelter for overwintering. Like Maculinea alcon, larvae of M. myrmicae are numerous in Myrmica nests and more numerous than those of Maculinea teleius. Since the larvae of Microdon feed on an abundance of young ant brood, they experience low level of scramble competition and although many may develop in an ant’s nest they have probably little effect on host colony fitness., Magdalena Witek ... [et al.]., and Obsahuje seznam literatury
Competition is a major force organizing ant communities and results in co-occurring species evolving different strategies for foraging and use of space. Territorial species, as top dominants exclude each other, while shaping the local ant communities both qualitatively and quantitatively. In this study we examined how two territorial species, Formica polyctena and Lasius fuliginosus, can coexist in adjacent territories over long periods of time, and whether they affect co-occurring species of ants in different ways. Field observations in the absence and in the presence of baits were carried out around a L. fuliginosus nest complex surrounded by a polydomous F. polyctena colony in S Finland in 2007–2009. Both species controlled their territories, but were affected by changes in the abundance of the other species and the distance from L. fuliginosus’ main nest. They did not have the same effect on the subordinate species in the absence of baits, but the abundance of Myrmica spp. recorded at baits was negatively affected by both of the territorial species. The preferences of the different species for the artificial food sources differed: L. fuliginosus and F. polyctena preferred tuna to honey and Myrmica spp. honey to tuna. More individuals of the subordinate species were recorded in the territory of F. polyctena than of L. fuliginosus, although conflicts with this territorial species were also recorded. During the three years of the study almost no overlaps in the territories of the two territorial species were recorded, and there were mostly minor shifts in the boundaries of the territories. Differences between the two territorial species in their use of space and competitive effects ensured their coexistence at this particular site in Finland., Wojciech Czechowski ... [et al.]., and Obsahuje seznam literatury